Some electronic systems and communication systems utilize biometrics, for example, methods which may be able to uniquely identify or recognize a particular person based on one or more intrinsic physical or behavioral traits. Such traits may include, for example, fingerprint, palm geometry, face recognition, iris or retina recognition, voice (e.g., speaker recognition), or other physiological characteristics, behavioral characteristics, “behaviometrics”, or the like.
Some systems may utilize biometrics, for example, for identity access management, for access control, or to identify an individual who is under surveillance. Some systems utilize biometrics for verification purposes; for example, the system performs a one-to-one comparison of a newly-captured biometric sample or utterance with a previously-stored sample or voice-print, in order to verify that the person is indeed the individual that he claims to be. Some systems utilize biometrics for recognition purposes; for example, the system performs a one-to-many comparison of a newly-captured biometric sample against a database of previously-captured biometric samples of multiple persons, in an attempt to identify an unknown individual.
Some systems of speaker recognition may utilize Text-Dependent (TD) methods or Text-Independent (TI) methods. For example, in a text-dependent method, an enrollment stage requires the speaker to say a particular phrase; the method then extracts features from the captured voice sample; and a subsequent verification or authentication stage requires the speaker to say, again, that particular phrase. A text-dependent method may be exposed to some security breaches; for example, an eavesdropper may intercept and record the authentic user uttering the pass-phrase (e.g., during the enrollment stage, during verification stage, or by doing “voice phishing” at a later point in time), and the eavesdropper may subsequently attempt to playback the recorded utterance, posing to be the authentic user.
In contrast, in a text-independent method, the phrase spoken during the enrollment stage is different from the phrase spoken during the verification stage; and the enrolment stage may be performed even without the actual knowledge of the user.